Antibiotics In Animal Feed May Also Be Increasing Global Drug-Resistant Bacteria

By R. Siva Kumar - 17 Apr '16 10:34AM

Even as the use of antibiotics increases in farming, the resistant genes to them may also be increasing globally.

Examining large-scale swine farms in China and one population of pigs in the U.S., scientists found many partner genes, which are resistance genes as well as mobile genetic elements found together. With the increase or decrease of one gene in abundance, the experts found that the partner genes kept pace.

As the Chinese farms are located close to bigger cities, monitoring antibiotic resistance in pigs is vital to reduce human risk. If there is a transference of antibiotic resistance, people can fall ill and need greater and more extensive treatment.

Moreover, some of the partner genes can make bacteria resist antibiotics that were not even given to the beasts. Perhaps, partner genes were present in the bacteria that were resistant to the antibiotics fed to the pigs.

"In the fight against the rise of antibiotic resistance, we need to understand that the use of one antibiotic or, in some cases, antibacterial disinfectants may increase the abundance of multidrug-resistant bacteria," said James Tiedje of MSU, one of the researchers. "Tracking the source of antibiotic resistance is quite complicated because antibiotic use, which increases the occurrence of resistance, is widespread, and antibiotic resistance can spread between bacteria."

As this is a global problem, scientists point out that "multidrug resistance is just a plane ride away."

"Our results clearly show the diversity of resistance genes on swine farms and that many genes likely originated from the same source," Tiedje said. "We also showed the linkage of resistance genes to each other as well as genes that enable them to be clustered in one bacteria or shared among bacteria. These findings will help guide practice and policies for prudent agricultural antibiotic use and to minimize antibiotic resistance genes spread to pathogens."

The findings were published on April 12, 2016,issue of the journal mBio.